Fast Terrain Following with LiDAR

Good morning, I’d like to be able to follow very hilly terrain at a high(er) velocity (15+m/s) and low altitude ( ~10 meters). Parameters in PX4 suggest max speed appears to be 4Mph. I’m not sure if this is a strict rule where the Lidar is no longer primary altitude sensor over 4mph or not. The lidar also seems to have a long delay (~1 sec.?) so at higher speeds, the drone can’t keep up with changing height AGL.
Is anyone else trying do something similar?
Thank you in advance!

Did you look at the manual Terrain Following/Holding | PX4 User Guide (main)

The docs say

At higher altitudes (when the estimator reports that the distance sensor data is invalid) the vehicle switches to altitude following , and will typically fly at a near-constant height above mean sea level (AMSL) using an absolute height sensor for altitude data.

So I suspect the settings are all around trusting the distance sensor data. Part of that might be deciding that since you’re travelling fast with a 1 second delay in data the value can’t be trusted.

What parameters are you looking at, PX4 version, type of lidar? Depending on how you respond might loop in someone more expert.

Thanks for your reply. I’ve read the docs. I’m using a Lidar Lite V3 which gives me accurate distance measurements well above my desired altitude AGL. It’s very slow to update, for example if I fly up a slope at a low velocity like 3 m/s I’m ok. If I’m going 10+ m/s I’m not tracking/updating fast enough and will cause an impact with terrain - if I let it go. I’d like to fly fast missions (15+ m/s) at low altitude( ~10m AGL) and track terrain.
So I guess my question is: do I have something wrong, or am I exceeding the capability of the lidar/PX4? If the latter is the case, is there anything you would suggest to improve performance?
Thanks again

Hello. Did you solve the problem?

No, PX4 blows bigtime

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